The present invention relates generally to the field of elevator control, and more particularly to providing a video aided system that improves elevator dispatch, door control, access control, and integration with security systems.
Elevator performance is derived from a number of factors. To a typical elevator passenger, the most important factor is time. As time-based parameters are minimized, passenger satisfaction with the service of the elevator improves. The overall amount of time a passenger associates with elevator performance can be broken down into three time intervals.
The first time interval is the amount of time a passenger waits in an elevator hall for an elevator to arrive, hereafter the “wait time”. Typically, the wait time consists of the time beginning when a passenger pushes an elevator call button, and ending when an elevator arrives at the passenger's floor. Methods of reducing the wait time have previously been focused on reducing the response time of an elevator, either by using complex algorithms to predict passenger demand for service, or reducing the amount of time it takes for an elevator to be dispatched to the appropriate floor.
The second time interval is the “door dwell time” or the amount of time the elevator doors are open, allowing passengers to enter or leave the elevator. It would be beneficial to minimize the amount of time the elevator doors remain open, after all waiting passengers have entered or exited an elevator cab.
The third time interval is the “ride time” or amount of time a passenger spends in the elevator. If a number of passengers are riding on the elevator, then the ride time may also include stops on a number of intermediate floors.
A number of algorithms have been developed to minimize the wait time a passenger spends in the elevator hall. For instance, some elevator control systems use passenger flow data to determine which floors to dispatch elevators to, or park elevators at, depending on the time of day. Typically, requesting deployment of an elevator by pushing the call button results in a single elevator being dispatched to the requesting floor. In situations in which the number of passengers waiting on the requesting floor is greater than the capacity of the elevator, at least some passengers will have to wait until after the first elevator leaves, and then push the call button again to request a second elevator be sent to the requesting floor. This results in an increase in the overall wait time for at least some of the passengers. In a similar situation, a particular elevator cab carrying the maximum number of passengers may continue to stop on floors requesting elevator service. Because no new passengers can enter the elevator, the ride time of passengers on the elevator is increased unnecessarily, as is the wait time for passengers in the elevator hall.
Many elevator systems are also integrated with access control and security systems. The goal of these systems is to detect, and if possible, prevent unauthorized users from gaining access to secure areas. Because elevators act as access points to many locations within a building, elevator doors and cabs are well suited to perform access control. A number of schemes have been devised to defeat traditional access control systems, such as “card pass back” and “piggybacking”. Card pass back occurs when an authorized user (typically using a card swipe) provides his card to an unauthorized user, allowing both the authorized user and the unauthorized user to gain access to a secure area. Piggybacking occurs when an unauthorized user attempts to use an authorization provided by an authorized user to gain access to a secure area (either with or without the knowledge of the authorized user).
Therefore, it would be useful to design an elevator system that could minimize wait times experienced by passengers, while providing improved security or access control.